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Where lies the line in the sand between Technological risks or technological idiocy? Would you accept to rely on a “perfect system” that has no bypasses, safety overrides? Such systems exist and people, corporations are flocking to use them. “Append only” systems We can interpret Blockchain as a “append only” distributed database with no central server. In addition a blockchain database has no ability to change or modify a record once it is added. That characteristic is called immutability. Immmutability…

A tale of hazards, risks and resilience came to my mind while in Venice, end of October. I lived though an extraordinary “acqua alta” (high tide) which submerged approximately 70% of the city and was reportedly the fifth event of such magnitude in 924 years. Aqua alta is a complex event combining high tide and wind driven surge in the Venetian Laguna: South winds hinder the tide outflow and “push” in the Laguna open sea water. Aqua alta is not…

Last week we focused on technical aspects of the Risk analysis of dam break. This week we go further by looking at societal tolerance and approaches. These may integrate ethical and economical approaches to these studies. Probability of failure and bench-marking of the case history dam A recent study of a tailings dam (centerline, rockfill, well investigated, built and monitored) using the ORE2_Tailings app delivered an estimate of the probability of failure. The result was pf in the 10-4 to…

Recent tailings disasters such as the failure of the Mount Polley and Samarco dams have focused the attention on the Consequences of tailings dams failures. Consequences of tailings dams failures: outflow volume and runout distance Classic approaches Various classic approaches (Rico et al., 2008, Azam & Li, 2010) assume that the volume of released tailings is a function of storage volume. Dam height intervenes, particularly for the runout distance preliminary evaluation. They find “statistical correlations” using a set of dam…

We all know that megaprojects including hydroelectric ones are subject to Cost and schedule risks. Experts recently confirmed this to the Commission of Inquiry Respecting the Muskrat Falls Hydroelectric Project. They said it is common for such projects to evolve with understated early cost estimates. That was the conclusion of a report which looks at 274 hydro dam projects around the world, including projects in Canada. Reportedly this is the largest academic data set of its kind in the world.…

Like we did in London last year, here are our Tailings and Mine Waste 2018 risk the good the bad and the ugly. The good It was very good to hear the John Lupo Keynote Lecture develop ideas about risk and the human element. He introduced to the audience biases and cognitive biases. He was able to get some amused reactions from the audience as he was explaining very important concepts. Let’s see if anyone will remember anything from his…

We received a number of questions from a reader interested in risk assessment. After we replied we thought these questions may be of general interest, so, here they are, with their answers. General questions from a reader interested in risk assessment Q1: On your website you use acronyms such as FTA and ETA what are these? A1: Failure Tree Analysis (FTA), Event Tree Analysis(ETA) are tools used to evaluate the probability of failure and/or the development of complex events starting…